Observation of surface Dirac state in transition metal dichalcogenide NiTe2 using ARPES

Abstract

Using angle resolved photoemission spectroscopy (ARPES) we studied the low energy electronic structure of transition metal dichalcogenide (TMDC), NiTe2, single crystal. Our ARPES data clearly show a surface Dirac point observed at a binding energy of 1.45 eV which is consistent with an earlier prediction. Thus, our results for the first time experimentally prove that NiTe2is a topological TMDC. Our ARPES data further suggest a metallic nature of NiTe2. We found that overall the electronic structure of NiTe2has similarities with the other topological TMDCs like PdTe2, PtTe2 and PtSe2.